Joined in 1967, Bell Labs was a corporation jointly owned by American Telephone and Telegraph Company and its subsidiary Western Electric. Soon after with Ken Thompson and others, first started work on Unix.

After Unix had become well established in the Bell System and in a number of educational, government and commercial installations, along with Steve Johnson and help by Ken Thompson, transported the operating system to the Interdata 8/32,
thus demonstrating its portability, and laying the groundwork for the widespread growth of Unix: the Seventh Edition version from the Bell Labs research group was the basis for commercial Unix System V and
also for the Unix BSD distributions from the University of California at Berkeley. The last important technical contribution made by Dennis Richie to Unix was the Streams mechanism for interconnecting devices, protocols, and applications.